What is imitation hard enamel?

Imitation hard enamel is invented in early 1990 and also named Soft cloisonne or synthetic cloisonne. It would be filled into the stamped metal first, and have polishing and electroplating afterwards. It is hard to tell the difference between real hard enamel and imitation hard enamel colors, but if you stab the color parts with knife point, imitation hard enamel colors will get visible marks, however real hard enamel colors won’t because hard enamel colors are as hard as tiles.